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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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My idle SUCKS! What can I do??

  • Thread starter Thread starter BlueOvalStangGT
  • Start date Start date Sep 12, 2005
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a50sn95

Founding Member
Oct 12, 2001
368
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16
Elk Grove, CA
Sep 14, 2005
#41
  • Sep 14, 2005
  • #41
final5-0 said:
I gotta tell ya, I dont think that tiny bit above 1.0 volts is hurting a thing as I have seen peeps dlogs that was a bit higher but they reported no idle issues.

It won't hurt to knock it down a bit that is for sure.

I got an idea that could help and will share it later tonight but I first got to do a little research and get my stuff together.

Grady
Click to expand...
I think over 1 volt puts it in "part throttle" vs "idle". I THINK there are different tables used, but I don't really know. I do know that CalCon says "part throttle"if you are datalogging throttle position, and the TPS voltageis over 1.
Dennis
 

BlueOvalStangGT

Active Member
Oct 27, 2003
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46
Tampa Florida....USF!!!
Sep 14, 2005
#42
  • Sep 14, 2005
  • #42
Ok I just set my idle, got it to around 900-1000 which is where it seemed to idle best. Any lower it would surge a little. If I gave it some gas and let go(like to 3k) it would dip down to like 600 and then come back up.I didnt have the time to mess with the TPS but tonight im gonna see what its at. Ill keep you all updated and im gonna make a small tune for it now too. What controls A/F mostly? Like what tables should I start with? Tonight Im just gonna turn off all the emmisions, bump idle to like 850(even though it idles at like 950) and do the small scalars I know how to do. Tomorow maybe ill try to enter in my flo sheet with EEC analyzer.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Sep 14, 2005
#43
  • Sep 14, 2005
  • #43
You guys might think this is crazy but I have a few thoughts based on a phone conversion a while back with Rockin Rick. We compared a few things and one thing we saw that was very close with our files was our tb air flow and isc neutral idle air flow values.

Keven has a pa combo and ours is na so this could just be wasted time but I wonder if, at idle, the blower may not contribute anything to the air flow.

My tb airflow is 0.9585 and a stock j4j1 has a value of 0.56

Here are 5 of my points of the 9 point isc table
704rpm is 0.89
800rpm is 0.96
992rpm is 1.03
1296rpm is 1.63
2000rpm is 2.48

Only 3 points match in a stock j4j1 and they are:
800rpm is 0.85
1296rpm is 1.35
2000rpm is 2.15

First of all, like Dennis, Rick and I did the correct procedures to arrive at those values.

Keven is in a situation of being away from home and no access to tools and the like so here is my idea that might help him and it seems logical to me plus.........it won't take but a few seconds to try.

Take the values of mine and Rick's and do the % thing between them and the stock j4j1 values I gave. Put the new values into play in whatever file Keven is using.

I can't see how it would hurt anything as were talking about idle and just a bit above and we are not under any kind of load that would matter.

Dennis it would be interesting to see what values you came up with for your file.

Anyway, that is my idea

btw ... I do think it is best to work through all of the steps to correctly arrive at those values. Then you know they are based from your very own combo and then the custom tune thing becomes a reality for you.

Grady
 

a50sn95

Founding Member
Oct 12, 2001
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Elk Grove, CA
Sep 14, 2005
#44
  • Sep 14, 2005
  • #44
Mine were in the link in that first post of mine:

Idle 750 RPM
TB Airflow: 1.6176
ISC Neutral Idle Airflow:
0 0 624 672 800 1008 1296 2000 1048560
0 0 1.438 1.46 1.69 2.1196 2.6997 4 4

Dashpot PrePosition:
900 1100 2500 3500 16384
0.5122 0.81934 0.81934 1.02392 1.02392

I must say I DO believe the Vortech pumps air at idle. That TB Airflow number is BIG compared to yours, and I only see about 12 pound of vacuum at idle. This cam isn't THAT big....
 

BlueOvalStangGT

Active Member
Oct 27, 2003
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46
Tampa Florida....USF!!!
Sep 14, 2005
#45
  • Sep 14, 2005
  • #45
UPDATE: I thought the car was idling good when I adjusted it but once it cooled down it was different. When cold the car wont idle AND my a/f is like 10.4 CRUISING. Once it warms up it idles better and for a while it actually idled good. Then after a while of driving the thing surges and doesnt idle well but the A/F leans out a little. MY tps is at .935 now too. Should I try to bump it up a little? What can I try next? Im gonnna load the MAF from caledit next and maybe even try loading in my flow sheet on EA.
 

a50sn95

Founding Member
Oct 12, 2001
368
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Elk Grove, CA
Sep 15, 2005
#46
  • Sep 15, 2005
  • #46
If you have the flowsheet for your MAF, use that one. The one in Caledit is the generic one you used to be able to get off their website. If you have the SC version of Pro-m's MAF, they are notoriously rich. Once I got my idle set, I moved on to the MAF. Use the WB, and adjust your MAF numbers at the flow rate you are rich at. Also watch you KAM numbers. Those are what the computer is seeing. If your WB says rich, and the KAM's are trying to lean it out (numbers under 1.00), then you can feel safe that everything is right. If not then maybe it's time for new O2's.
If you have EA, it will make adjusting your MAF easier, but you CAN just sit in the driveway and move the idle and part throttle numbers pretty safely. I wouldn't mess with the A/F tables until you get your MAF right, because if you change you MAF later, all those numbers have to be revisited.
So, If you idle with your MAF at .75 volts, and you are reading 11.00 for the AFR, change the number in your MAF transfer to a smaller number, to lean it out. I'd do tiny steps until you have a feel for how much chagne it's making....
Dennis
 

scarless

Member
Aug 9, 2004
175
0
16
Sep 15, 2005
#47
  • Sep 15, 2005
  • #47
Maybe this will help. It says to 93, but I think it'll work on 94/95's too.

http://secure.50resto.com/product1....ID=ly55E9RJM57R56XAVWbC&SID=1&Product_ID=2123
 

a50sn95

Founding Member
Oct 12, 2001
368
0
16
Elk Grove, CA
Sep 15, 2005
#48
  • Sep 15, 2005
  • #48
No worky...
 

a50sn95

Founding Member
Oct 12, 2001
368
0
16
Elk Grove, CA
Sep 15, 2005
#49
  • Sep 15, 2005
  • #49
http://secure.50resto.com/product1.cfm?SID=1&Product_ID=2123
How about this one? (Your link had session information, which had expired...)
If so, then You don't need it. Our throttle bodies have it already. Look up at the picture I posted. The one that says ISC Bypass adjust. Same thing....
 

ShiftTheDrift

New Member
Dec 16, 2002
365
0
0
Bakersfield, CA
Sep 15, 2005
#50
  • Sep 15, 2005
  • #50
tid bit more info..
Solving Idle Problems Part 1
 

BlueOvalStangGT

Active Member
Oct 27, 2003
2,849
0
46
Tampa Florida....USF!!!
Sep 15, 2005
#51
  • Sep 15, 2005
  • #51
a50sn95 said:
If you have the flowsheet for your MAF, use that one. The one in Caledit is the generic one you used to be able to get off their website. If you have the SC version of Pro-m's MAF, they are notoriously rich. Once I got my idle set, I moved on to the MAF. Use the WB, and adjust your MAF numbers at the flow rate you are rich at. Also watch you KAM numbers. Those are what the computer is seeing. If your WB says rich, and the KAM's are trying to lean it out (numbers under 1.00), then you can feel safe that everything is right. If not then maybe it's time for new O2's.
If you have EA, it will make adjusting your MAF easier, but you CAN just sit in the driveway and move the idle and part throttle numbers pretty safely. I wouldn't mess with the A/F tables until you get your MAF right, because if you change you MAF later, all those numbers have to be revisited.
So, If you idle with your MAF at .75 volts, and you are reading 11.00 for the AFR, change the number in your MAF transfer to a smaller number, to lean it out. I'd do tiny steps until you have a feel for how much chagne it's making....
Dennis
Click to expand...

I just put in brand new o2 sensors with the new motor. How can I tell what my idle numbers are if the car doesnt idle? What A/F should I have at idle, cruising(part throttle) and at WOT?
 

a50sn95

Founding Member
Oct 12, 2001
368
0
16
Elk Grove, CA
Sep 15, 2005
#52
  • Sep 15, 2005
  • #52
BlueOvalStangGT said:
How can I tell what my idle numbers are if the car doesnt idle?
Click to expand...

You can't. You really need to get it to idle. I don't think it's going to idle reliably until you make the TB airflow and ISCNeutral Idle Airflow numbers changed. Until then, the computer is just making bad calculations, because it has bad numbers for those items.

BlueOvalStangGT said:
What A/F should I have at idle, cruising(part throttle) and at WOT?
Click to expand...
Your fuel tables tell you what it is targeting. You can also datalog commanded A/F, and watch your wideband. If it's commanding 14.7 and your seeing 10, you need to lean itout at that airflow number.
Closed loop idle should be close to 14.7, but you are really trying tomake it match "commaneded" Once it matches, and it's not where you want it, then you can start figuring that one out.

Get the idle first. Don't try to work on more than one thing at a time, or you won't know what is causing the changes you are seeing....
 
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